1. Field of the Invention
The present invention relates to a human thymosin β-4 (Tβ4)-mimicking peptide and its uses.
2. Description of the Related Art
Hair is an organelle of which growth is complicatedly regulated by various growth factors depending on the growth steps of hair follicles. The differentiation of hair follicles and the related hair cycle are generally divided into several stages: hair-growing anagen; catagen in which hair loss is observed; telogen in which hair growth is arrested; and new anagen in which new hair is generated and grows (Paus, R., et. Al and Cotsarelis, G. (1999) The biology of hair follicles. N. Engl. J. Med. 341, 491-497).
Anagen stage, in which hair is growing, is divided into two sub-stages: one is the step of starting to generate hairs to come out from hair bulbs to hair follicles, and the other is the step of forming stiff keratin in hair follicles. Hairs continue the self-growth until the catagen stage. The life span of hairs in the anagen stage ranges from 3 to 6 years. Hairs in the anagen stage occupy 80-90% of total hairs (100,000-150,000 hairs) and grow about 1-1.5 cm during one month.
In catagen stage after anagen stage, the metabolism of hairs becomes to be slower with maintaining the shape of hairs and hair grows slowly. In addition, keratin is not formed in this stage. The catagen stage continues for 1-1.5 months and occupies 1% of total hairs. Hair bulb is contracted to be divided into hair papilla, which are surrounded by hair follicles and in turn is mobilized to upper part. The cell division is shown to be arrested at this time.
In telogen stage, hair papilla are shrunk, hair follicle is gradually contracted, and the hair root is pushed upward to be finally removed (the part of the hair root is raised upward and the depth of hair follicles become to be decreased by ⅓). This stage is characterized by hair loss and continues for 3-4 months. Hairs in telogen stage occupy 4-14% of total hairs (occupies 30-40% after birth) and easily falls out by only strong combing or stimulus.
Lastly, at the new anagen, hair bulbs which is surrounded by hair follicles in the anagen stage, combines with hair papilla to induce the formation of new hairs. Afterwards, the new hairs push upward and naturally remove old hairs in the talogen stage.
The hair cycles described previously are unlikely to occur in the same pattern. Hair cycles can be varied depending on the conditions such as diseases, heredity, body conditions and age. For example, some abnormalities such as the new anagen with non-terminated telogen, the angen without terminal hairs and the entrance of catagen with soft terminal hairs may be found.
Furthermore, as the society becomes more complex, factors facilitating hair loss such as environmental pollution, stress and numerous chemical compounds gradually increase. Therefore, the number of people suffering from hair loss tends to increase.
However, compounds or substances capable of preventing evidently hair loss or promoting hair growth have not yet proposed. Accordingly, there remains a need in the art to develop novel substances to facilitate hair growth.
Thymosin beta-4 (Tβ4) has been discovered in cow thymus in the year of 1981. Tβ4 is a weakly acidic protein consisting of 44 amino acids having a molecular weight of 4.982 kDa, and having a theoretical isoelectric point of 5.1. Tβ4 has many polar amino acids such as glutamine and lysine residues. For example, Tβ4 has 11 aspartic acid and glutamine residues, and 9 lysine and arginine residues. FIG. 1 represents the putative secondary structure of Tβ4 comprising two helical structures.
It has been known to one of skill in the art that Tβ4 plays a crucial role as a regulator in cell migration and differentiation and is also involved in the wound healing and angiogenesis (Frohm, M., Gunne, H., Bergman, A. C., Agerberth, B., Bergman, T, Boman, A., Liden, S., Jornvall, H., and Boman, H. G. (1996) Biochemical and antibacterial analysis of human wound and blister fluid. Eur. J. Biochem. 237, 86-92).
However, a natural-occurring form of Tβ4 is very likely to show reduced treatment efficacies because such a form is neither biologically unstable nor physically homogenous. In addition, there is also a serious problem of relatively low skin permeation potency of Tβ4 in the natural form.
Accordingly, there remain long-felt needs to develop novel approaches for improving the stability and skin permeation of Tβ4.
Throughout this application, various patents and publications are referenced and citations are provided in parentheses. The disclosure of these patents and publications in their entities are hereby incorporated by references into this application in order to more fully describe this invention and the state of the art to which this invention pertains.